Thermo Scientific Accela UV/Vis Plus, Hardware Manual

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3
Routine Maintenance
Lamp Maintenance
50 Accela UV/Vis Detector Hardware Manual Thermo Scientific
5. To read the chronometer, check the position of the electrolyte gap in the mercury tube
against the graduated background (see Figure 49 and Figure 50 ).
Figure 49. Chronometer for the deuterium lamp
Figure 50. Electrolyte gap in the mercury tube at 400 hours
Removing the Deuterium Lamp
 To remove the deuterium lamp
1. Remove the deuterium lamp cover as described in “Accessing the Deuterium Lamp and
Reading Its Chronometer” on page 49 .
2. Gently unplug the deuterium lamp lead from the detector (see Figure 51 ). Take care not
to twist the connector.
Note
Two mercury columns separated by a small electrolyte gap fill the glass capillary
tubing that is visible in the chronometer window. With lamp usage, the mercury
column on the left side of the gap increases and the mercury column on the right side
of the gap decreases. This transfer of mercury moves the gap from left to right as a
function of lamp usage.
0
2000
HOURS
Lamp usage marker
at 400 hours